NURS 5450 Exam 2 - OB Anesthesia: Questions With
Easy-to-Follow Solutions
A 31-year-old female with a 24-week gestation presents for an appendectomy.
- How does pregnancy complicate the management of this patient?
- What are the potentially detrimental effects of surgery and anesthesia on the
fetus? Correct Answer -
When is the fetus most sensitive to teratogenic influences? Correct Answer
- 15-56 days???
What would be the ideal anesthetic technique for a 31-year-old female with a
24-week gestation needing an appy? Correct Answer -
Are any special monitors indicated perioperatively for a 31-year-old female
with a 24-week gestation needing an appy? Correct Answer - Fetal heart
montior +/- TOCO
When should elective operations be performed during pregnancy? Correct
Answer - NEVER
The cardiovascular changes in pregnant women are characterized by:
Correct Answer - - An increase in intravascular fluid volume
- An increase in cardiac output (CO)
- A decrease in systemic vascular resistance (SVR)
At term, plasma volume ↑by ____% Correct Answer - 45
Erythrocyte volume ↑by ____% Correct Answer - 20
Disproportionate plasma volume to erythrocyte volume increase results in the
relative _____ of pregnancy Correct Answer - anemia
The increased intravascular volume offsets the _______ ml of EBL associated
with vaginal delivery and the ________ ml of EBL associated with c-section
Correct Answer - 300-500; 800-1000
,The increased intravascular volume in a pregnant woman's blood dilutes the
__________. Correct Answer - plasma protein concentration
What happens to cardiac output during pregnancy? Correct Answer - -
10% increase by the 10th week of gestation
- 40-50% by the third trimester
Why does cardiac output increase during pregnancy? Correct Answer -
Result of a 25-30% increase in stroke volume and a 15-25% increase in HR
CO can increase by as much as ___% immediately following delivery. Correct
Answer - 80
Parturients with _______ (fixed valvular stenosis) at increased risk of increased
cardiac output after delivery. Correct Answer - cardiac disease
CO returns to near pre-pregnant values by ______ postpartum Correct
Answer - 2 weeks
What causes the decrease in SVR in pregnant women? Correct Answer -
Largely compensatory to offset the effects that would otherwise be seen with
the increases in blood volume and CO
How much does SVR decrease in pregnant women? Correct Answer -
Overall SVR is reduced by 20%
Femoral venous pressure ↑due to ___ by the gravid uterus. Correct Answer -
vena cava compression
What is the Aortocaval Compression that occurs in pregnancy associated
with? Correct Answer - - Associated with the supine position which
reduces venous return (preload) due to vena cava compression by the gravid
uterus
What causes the lower extremity venous stasis (ankle edema, hemorrhoids
and varicose veins) in pregnancy? Correct Answer - Aortocaval
Compression
, What is the acute presentation of aortocaval compression? Correct Answer
- Diaphoresis, N & V, changes in cerebration (Supine Hypotension
Syndrome), fetal distress
Aortocaval Compression is ________ . Correct Answer - Potentially worsened
by regional anesthetics (sympathectomy)
Aortocaval Compression Correct Answer -
What are the pregnant woman's compensatory mechanisms for
aortocaval compression? Correct Answer - - The increased IVC pressure
below the gravid uterus results in diversion of a large portion of the venous
return to the paravertebral venous plexuses →azygous vein →SVC thereby
maintaining preload (regional anesthesia implications)
- Reflex peripheral SNS response which increases SVR and sustains B/P
Regional Implications of IVC Compression (image) Correct Answer -
What is the symptomatic management of aortocaval compression? Correct
Answer - - Left uterine displacement a.k.a. lateral tilt
- Oxygen
- Hydration
- Pressor agents as needed
Left uterine displacement a.k.a. lateral tilt (image) Correct Answer -
What upper airway changes occur during pregnancy? Correct Answer - -
Capillary engorgement of the upper airway
- Edematous vocal cords and arytenoids
- Weight gain +/-pre-existing obesity +/-short neck and large breasts
- CAREFUL instrumentation of airway (laryngoscopy, suctioning, oral (nasal)
airway placement)
- Smaller ETT tubes
What happens to minute ventilation during pregnancy? Correct Answer - -
50% overall increase (40% ↑in VT; 15% ↑RR)
- Mediated by ↑progesterone
- Resting PaCO2 ↓to 32 mm Hg from 40 mm Hg
- pH unchanged due to increased renal excretion of bicarbonate
Easy-to-Follow Solutions
A 31-year-old female with a 24-week gestation presents for an appendectomy.
- How does pregnancy complicate the management of this patient?
- What are the potentially detrimental effects of surgery and anesthesia on the
fetus? Correct Answer -
When is the fetus most sensitive to teratogenic influences? Correct Answer
- 15-56 days???
What would be the ideal anesthetic technique for a 31-year-old female with a
24-week gestation needing an appy? Correct Answer -
Are any special monitors indicated perioperatively for a 31-year-old female
with a 24-week gestation needing an appy? Correct Answer - Fetal heart
montior +/- TOCO
When should elective operations be performed during pregnancy? Correct
Answer - NEVER
The cardiovascular changes in pregnant women are characterized by:
Correct Answer - - An increase in intravascular fluid volume
- An increase in cardiac output (CO)
- A decrease in systemic vascular resistance (SVR)
At term, plasma volume ↑by ____% Correct Answer - 45
Erythrocyte volume ↑by ____% Correct Answer - 20
Disproportionate plasma volume to erythrocyte volume increase results in the
relative _____ of pregnancy Correct Answer - anemia
The increased intravascular volume offsets the _______ ml of EBL associated
with vaginal delivery and the ________ ml of EBL associated with c-section
Correct Answer - 300-500; 800-1000
,The increased intravascular volume in a pregnant woman's blood dilutes the
__________. Correct Answer - plasma protein concentration
What happens to cardiac output during pregnancy? Correct Answer - -
10% increase by the 10th week of gestation
- 40-50% by the third trimester
Why does cardiac output increase during pregnancy? Correct Answer -
Result of a 25-30% increase in stroke volume and a 15-25% increase in HR
CO can increase by as much as ___% immediately following delivery. Correct
Answer - 80
Parturients with _______ (fixed valvular stenosis) at increased risk of increased
cardiac output after delivery. Correct Answer - cardiac disease
CO returns to near pre-pregnant values by ______ postpartum Correct
Answer - 2 weeks
What causes the decrease in SVR in pregnant women? Correct Answer -
Largely compensatory to offset the effects that would otherwise be seen with
the increases in blood volume and CO
How much does SVR decrease in pregnant women? Correct Answer -
Overall SVR is reduced by 20%
Femoral venous pressure ↑due to ___ by the gravid uterus. Correct Answer -
vena cava compression
What is the Aortocaval Compression that occurs in pregnancy associated
with? Correct Answer - - Associated with the supine position which
reduces venous return (preload) due to vena cava compression by the gravid
uterus
What causes the lower extremity venous stasis (ankle edema, hemorrhoids
and varicose veins) in pregnancy? Correct Answer - Aortocaval
Compression
, What is the acute presentation of aortocaval compression? Correct Answer
- Diaphoresis, N & V, changes in cerebration (Supine Hypotension
Syndrome), fetal distress
Aortocaval Compression is ________ . Correct Answer - Potentially worsened
by regional anesthetics (sympathectomy)
Aortocaval Compression Correct Answer -
What are the pregnant woman's compensatory mechanisms for
aortocaval compression? Correct Answer - - The increased IVC pressure
below the gravid uterus results in diversion of a large portion of the venous
return to the paravertebral venous plexuses →azygous vein →SVC thereby
maintaining preload (regional anesthesia implications)
- Reflex peripheral SNS response which increases SVR and sustains B/P
Regional Implications of IVC Compression (image) Correct Answer -
What is the symptomatic management of aortocaval compression? Correct
Answer - - Left uterine displacement a.k.a. lateral tilt
- Oxygen
- Hydration
- Pressor agents as needed
Left uterine displacement a.k.a. lateral tilt (image) Correct Answer -
What upper airway changes occur during pregnancy? Correct Answer - -
Capillary engorgement of the upper airway
- Edematous vocal cords and arytenoids
- Weight gain +/-pre-existing obesity +/-short neck and large breasts
- CAREFUL instrumentation of airway (laryngoscopy, suctioning, oral (nasal)
airway placement)
- Smaller ETT tubes
What happens to minute ventilation during pregnancy? Correct Answer - -
50% overall increase (40% ↑in VT; 15% ↑RR)
- Mediated by ↑progesterone
- Resting PaCO2 ↓to 32 mm Hg from 40 mm Hg
- pH unchanged due to increased renal excretion of bicarbonate
